The Clovis culture
(sometimes referred to as the Llano culture
) is a prehistoric Paleoindian
culture that first appears in the archaeological
record of North America
around 11,500 rcbp radiocarbon years
ago, at the end of the last glacial period
. Archaeologists' best guess at present suggests this is equal to roughly 13,000 calendar years ago. The Clovis culture is thought to have lasted from between 200 and 800 years, depending on the source consulted, with an average estimate of around 500 years, starting about 13,000 years ago. The Clovis culture was replaced by several more localized regional cultures from the time of the Younger Dryas
cold climate period onward. Post-Clovis cultures include the Folsom tradition
, Gainey, Suwannee-Simpson, Plainview-Goshen, Cumberland point, and Redstone. Each of these is commonly thought to derive directly from Clovis, in some cases apparently differing only in the length of the fluting on their projectile points. Although this is generally held to be the result of normal cultural change through time, numerous other reasons have been suggested to be the driving force for the observed changes in the archaeological record, such as an extraterrestrial impact event
or post-glacial climate change with numerous extinctions.
The Clovis people, one of the several distinct Paleoindian groups mentioned above, were regarded as the first human inhabitants of the New World since the discovery of several Clovis sites in western North America in the 1930s. Clovis people were thought to be the ancestors of all the indigenous cultures of North and South America. However, this view has been contested over the last thirty years by several archaeological discoveries, including sites like Cactus Hill in Virginia, Paisley Caves in the Summer Lake Basin of Oregon, Meadowcroft Rockshelter in Pennsylvania, and Monte Verde, Chile.
The culture was originally named for a small number of artifacts found in 1936 and 1937 at Blackwater Draw
Locality #1, near Portales, New Mexico
. People began collecting artifacts at this site in the late 1920s but artifacts and animal remains that had not moved since the Pleistocene were not recovered until 1936. The in situ finds of 1936 and 1937 included stone Clovis points, two long bone points with impact damage, stone blades, a portion of a Clovis blade core, and several cutting tools made on stone flakes. Clovis sites have since been identified throughout much, but not all, of the contiguous United States
, as well as Mexico
and Central America
, and even into Northern South America.
A hallmark of the toolkit associated with the Clovis culture is the distinctively-shaped fluted stone spear point, known as the Clovis point. The Clovis point is bifacial and typically fluted on both sides. Archaeologists do not agree on whether the widespread presence of these artifacts indicates the proliferation of a single people, or the adoption of a superior technology by diverse population groups. It is generally accepted that Clovis people hunted mammoth as Clovis points have repeatedly been found in sites containing mammoth remains. Mammoth is only a small part of the Clovis diet; extinct bison, mastodon, sloths, tapir, palaeolama, horse and a host of smaller animals have also been found in Clovis sites where they were killed and eaten. In total, more than 125 species of plants and animals are known to have been used by Clovis people in the portion of the Western Hemisphere they inhabited. Clovis sites are known from most of North America, some parts of Central America, and even into northern South America in Venezuela (see Pearson and Ream 2005).
Disappearance of Clovis
The most commonly held perspective on the end of the Clovis culture is that a decline in the availability of megafauna
, combined with an overall increase in population, led to local differentiation of lithic and cultural traditions across the Americas. After this time, Clovis-style fluted points disappear, although other fluted-point traditions (such as the Folsom culture
) continue essentially uninterrupted. An effectively continuous cultural adaptation proceeds from the Clovis period through the ensuing Late Paleoindian. However, it has also been argued by others that Clovis ended more abruptly.
Whether the Clovis culture drove the mammoth, and other species, to extinction via overhunting — the so-called Pleistocene overkill hypothesis — is still an open, and controversial, question. The greater likelihood is that climate change possibly potentiated by human predation, disease, and additional pressures from newly arrived herbivores (competition) and carnivores (predation) and isolation made it impossible for them to reproduce and survive. It has also been hypothesized that the Clovis culture saw its decline in the wake of the Younger Dryas cold phase. This 'cold shock' lasting roughly 1,500 years affected many parts of the world, including North America. It appears to have been triggered by a vast meltwater lake — Lake Agassiz — emptying into the North Atlantic, disrupting the thermohaline circulation.
A recent hypothesis posits that one or more extraterrestrial bodies caused the mass extinction and triggered a period of climatic cooling. The Younger Dryas impact event proposal suggests that an extraterrestrial object such as a comet exploded in Earth's atmosphere above North America's Great Lakes region about 12,900 years ago, and significantly impacted the human Clovis culture. Though the "Clovis comet" hypothesis is not universally accepted, scholars have actively debated the controversial theory. It drew new scrutiny at a recent annual meeting of the Society for American Archaeology in Vancouver, Canada. An apparent association of the last Clovis artifacts and an organic stratigraphic layer laid down during the Younger Dryas has been noted:
At sites stretching from California to the Carolinas and as far north as Alberta and Saskatchewan, researchers have long noted an enigmatic layer of carbon-rich sediment that was laid down nearly 13 millennia ago. "Clovis artifacts are never found above this black mat," says Allen West, a geophysicist with Geoscience Consulting in Dewey, Ariz. The layer, typically a few millimeters thick, lies between older, underlying strata that are chock-full of mammoth bones and younger, fossilfree sediments immediately above.
The occurrence of several types of black mats was documented by C. Vance Haynes at two-thirds of 97 North American geoarchaeological sites he examined dating to the termination of the Clovis people and the Pleistocene-Holocene transition. In his abstract Haynes notes: "Recent evidence for extraterrestrial impact, although not yet compelling, needs further testing because a remarkable major perturbation occurred at 10,900 B.P. that needs to be explained."
Given Lake Agassiz' location just north of the Great Lakes, and the proposed impact site above the Great Lakes, it is possible that both theories are correct -- that the glaciers around the Great Lakes were impacted, spilling Lake Agassiz into those lakes, out the St. Lawrence, and into the Atlantic.
A cowboy and former slave, George McJunkin, found an Ancient Bison
(an extinct relative of the American Bison
) skeleton, probably with Paleoindian artifacts, in 1908 after a massive flood. It was first excavated in 1926, near Folsom, New Mexico
under the direction of Harold Cook and Jesse Figgins. On August 29th, 1927 they found the first in situ Folsom point
with the extinct Bison antiquus bones. This confirmation of a human presence in the America's during the PLeistocene inspired many people to start looking for evidence of Early Man. The finds at Clovis came to light very quickly after Folsom.
In 1929, 19-year-old James Ridgley Whiteman, discovered the Clovis Man Site in the Blackwater Draw in Eastern New Mexico. Despite earlier legitimate Paleoindian discoveries, the best documented evidence of the Clovis tool complex was excavated between 1932 and 1937 near Clovis, New Mexico, by a crew under the direction of Edgar Billings Howard from the Philadelphia Academy of Natural Sciences/University of Pennsylvania. Howard's crew left their excavation in Burnet Cave, New Mexico (truly the first professionally excavated Clovis site) in August, 1932 and visited Whiteman and his Blackwater Draw site. In November, Howard was back at Blackwater Draw to investigate additional finds by Whiteman.
There may be earlier reports of the Paleoindian layers of the dig in Burnet Cave, but it seems likely that the first report of professional work at a Clovis site concerns the Blackwater Draw site in the November 25, 1932 issue of Science News. This directly contradicts statements by some authors (Haynes 2002:56 The Early Settlement of North America) that Dent, Colorado was the first excavated Clovis site. The Dent Site, in Weld County, Colorado, was simply a fossil mammoth excavation in 1932. The first Dent Clovis point was found July 7, 1933. The in situ Clovis point from Burnet Cave was excavated in late August, 1931 and E. B. Howard brought it to the 3rd Pecos Conference and showed it around (see Woodbury 1983).
The predominant hypothesis (known as "Clovis First") among archaeologists in the latter half of the 20th century had been that the people associated with the Clovis culture were the first inhabitants of the Americas. The primary support for this was that no solid evidence of pre-Clovis human inhabitation had been found. According to the standard accepted theory, the Clovis people crossed the Beringia
land bridge over the Bering Strait
during the period of lowered sea levels during the ice age, then made their way southward through an ice-free corridor east of the Rocky Mountains
in present-day western Canada
as the glaciers
retreated. This hypothesis is rapidly losing ground as there is increasing evidence of human habitation predating the Clovis culture.
Evidence of human habitation before Clovis
Archaeologists have long debated the possible existence of a culture older than Clovis in North and South America.
Predecessors of the Clovis people may have migrated south along the North American coastline. According to researchers Michael Waters and Thomas Stafford of Texas A&M University, new radiocarbon dates place Clovis remains from the continental United States in a shorter time window (13,050 to 12,800 years ago), while radiocarbon dating of the Monte Verde site in Chile place Clovis-like culture there as early as 13,500 years ago and remains found at the Channel Islands of California place coastal Paleoindians there 12,500 years ago. This suggests that the Paleoindian migration could have spread more quickly along the coastline south, and that populations that settled along that route could have then began migrations eastward into the continent.
In 2004, worked stone tools were found at Topper in South Carolina that have been dated by radiocarbon techniques to 50,000 years ago, although there is significant dispute regarding these dates.. A more substantiated claim is that of Paisley Caves, where rigorous carbon-14 and genetic testing appears to indicate that humans related to modern Native Americans were present in the caves over 1000 14C years before the earliest evidence of Clovis. A study published in Science presents strong evidence that humans occupied sites in Monte Verde, at the tip of South America, as early as 13,000 years ago. If this is true then humans must have entered North America long before the Clovis Culture - perhaps 16,000 years ago.
The Tlapacoya site on the shore of the former Lake Chalco reveals bones, hearths, middens, and a curved obsidian blade, presumed to date to over 21,700 years BP, although the dating has been disputed.
Coastal migration route
Recent studies of the mitochondrial DNA
of First Nations
suggest that the people of the New World may have diverged genetically from Siberians as early as 20,000 years ago, far earlier than the standard theory would suggest. According to one alternative theory, the Pacific
coast of North America may have been free of ice such as to allow the first peoples in North America to come down this route prior to the formation of the ice-free corridor in the continental interior. No solid evidence has yet been found to support this hypothesis except that genetic analysis of coastal marine life indicates diverse fauna persisting in refugia throughout the Pleistocene ice ages along the coasts of Alaska and British Columbia; these refugia include common food sources of coastal aboriginal peoples, suggesting that a migration along the coastline was feasible at the time.
The controversial Solutrean hypothesis
proposed in 1999 by Smithsonian archaeologist Dennis Stanford
and colleague Bruce Bradley
(Stanford and Bradley 2002), suggests that the Clovis people could have inherited technology from the Solutrean
people who lived in southern Europe 21,000-15,000 years ago, and who created the first Stone Age
artwork in present-day southern France
. The link is suggested by the similarity in technology between the projectile points of the Solutreans and those of the Clovis people. Such a theory would require that the Solutreans crossed via the edge of the pack ice in the North Atlantic Ocean
that then extended to the Atlantic coast of France. They could have done this using survival skills similar to those of the modern Inuit
people. Supporters of this hypothesis suggest that stone tools found at Cactus Hill
(an early American site in Virginia
), that are knapped in a style between Clovis and Solutrean. Other scholars such as Emerson F. Greenman and Remy Cottevieille-Giraudet have also suggested a Northern Atlantic point of entry, citing toolmaking similarities between Clovis and Solutrean-era artifacts.
University of New Mexico anthropologist Lawrence G. Straus, a primary critic of the Solutrean hypothesis, points to the theoretical difficulty of the ocean crossing, a lack of Solutrean-specific features in pre-Clovis artifacts, as well as the lack of art (such as that found at Lascaux in France) among the Clovis people, as major deficiencies in the Solutrean hypothesis. The 3,000 to 5,000 radiocarbon year gap between the Solutrean period of France and Spain and the Clovis of the New World also makes such a connection problematic (Straus 2000). In response, defenders of the hypothesis state that the Solutreans introduced a tool-making innovation and not necessarily cultural or artistic practices.
Recent genetic studies
Mitochondrial DNA analysis (see Map in Single-origin hypothesis
) has found that some members of some native North American tribes have a maternal ancestry (called haplogroup X
) (Schurr 2000) linked to the maternal ancestors of some present day individuals in western Asia and Europe, albeit distantly.
An article in the American Journal of Human Genetics states "Here we show, by using 86 complete mitochondrial genomes, that all Native American haplogroups, including haplogroup X, were part of a single founding population, thereby refuting multiple-migration models." The study also argues for a Beringian isolation and subsequent coastal migration. However the study, which extrapolates from modern genetic specimens, addresses only the genetics of surviving populations and does not rule out the possibility of secondary Population bottleneck events having occurred at the time of the Younger Dryas.
Other possible pre-Clovis sites
In approximate reverse chronological order:
- Lagoa Santa, Minas Gerais, Brazil, is erroneously asserted to be Clovis age or even possibly Pre-Clovis in age. The recent discussion of this site (specifically Lapa Vermelha IV) and the Luzia skull- reportedly 11,500 years old by Neves and Hubb, makes it clear that this date is a chronological date in years Before Present and NOT a raw radiocarbon date in eastern Brazil. Clovis sites mostly date between 11,500 and 11,000 radiocarbon years which means 13,000 years before present at a minimum. "Luzia" is at least 1,000 years younger than Clovis and Lapa Vermelha IV should NOT be considered a Pre-Clovis site.
- The Big Eddy Site in southwestern Missouri contains several claimed pre-Clovis artifacts or geofacts. In situ artifacts have been found in this well-stratified site in association with charcoal. Five different samples have been AMS dated to between 11,300 to 12,675 BP (Before Present).
- Monte Verde II, a site in Chile, was occupied from 11,800 to 12,000 to years BP.
- Taima Taima, Venezuela has cultural material very similar to Monte Verde II, dating to 12,000 years BP.
- A cut mastodon tusk found at Page-Ladson, Jefferson County, Florida on the Aucilla River has been dated to 12,300 years BP near a few in situ artifacts of similar age.
- The Schaefer and Hebior mammoth sites in Kenosha County, Wisconsin indicate exploitation of this animal by humans. The Schaefer Mammoth site has over 13 highly purified collagen AMS dates and 17 dates on associated wood dating it to 12,300-12,500 radiocarbon years before the present. Hebior has two AMS dates in the same range. Both animals show conclusive butchering marks and associated non-diagnostic tools.
- A site in Walker, Minnesota with stone tools, alleged to be from 13,000 to 15,000 years old based on surrounding geology, was discovered in 2006.
- Human coprolites have been found in Paisley Caves in Oregon, carbon dated at 14,300 years ago. Genetic analysis revealed that the coprolites contained mtDNA haplogroups A2 and B2, two of the five major Native American mtDNA haplogroups.
- The Mud Lake site, in Kenosha County, Wisconsin consists of the foreleg of a juvenile mammoth recovered in the 1930s. Over 100 stone tool butchering marks are found on the bones. Several purified collegen AMS dates show the animal to be 13,450 rcybp with a range of plus or minus 1,500 rcybp variance.
- Meadowcroft Rockshelter in southwestern Pennsylvania, excavated 1973-78, with evidence of occupancy dating back from 16,000 to 19,000 years ago.
- Cactus Hill in southern Virginia, with artifacts such as unfluted bifacial stone tools with dates ranging from c. 15,000 to 17,000 years ago.
- Dixon, E. James (1999). Bones, Boats and Bison: Archeology and the First Colonization of Western North America. Albuquerque: University of New Mexico Press.
- Schurr, Theodore G. (2000). "Mitochondrial DNA and the Peopling of the New World". American Scientist 88 (3): pp.246–253.
- Stanford, Dennis; and Bruce Bradley (2002). "Ocean Trails and Prairie Paths? Thoughts About Clovis Origins.". The First Americans: The Pleistocene Colonization of the New World (Memoirs of the California Academy of Sciences, No. 27.), pp.255–271. ISBN 0-940-22849-1. .
- Straus, Lawrence G. (2000). "Solutrean Settlement of North America? A Review of Reality". American Antiquity 65 (2): pp.219–226.